Problem: hash in subscribe newHeads differs from eth_getBlockByNumber

[mmsqe]

Closes: #XXX

instead of overwriting hash field, seems SetFmtHash in txhash-v038x also allow us align eth tx hash in long term

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[codecov]

Codecov Report

Attention: Patch coverage is 33.33333% with 28 lines in your changes missing coverage. Please review.

Project coverage is 60.50%. Comparing base (452b0cf) to head (8ea16e2).

Files with missing lines	Patch %	Lines
rpc/stream/rpc.go	0.00%	18 Missing ⚠️
rpc/backend/blocks.go	50.00%	3 Missing and 3 partials ⚠️
rpc/backend/utils.go	80.00%	1 Missing and 1 partial ⚠️
rpc/types/utils.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #521      +/-   ##
===========================================
- Coverage    60.59%   60.50%   -0.10%     
===========================================
  Files          128      128              
  Lines         9724     9757      +33     
===========================================
+ Hits          5892     5903      +11     
- Misses        3255     3273      +18     
- Partials       577      581       +4     

Files with missing lines	Coverage Δ
rpc/backend/utils.go	49.71% <80.00%> (+1.83%)	⬆️
rpc/types/utils.go	0.00% <0.00%> (ø)
rpc/backend/blocks.go	82.51% <50.00%> (-1.60%)	⬇️
rpc/stream/rpc.go	0.00% <0.00%> (ø)